The invention relates to an agricultural vehicle such as a tractor configured with a coupling for mounting a mounted implement and, a mounted implement suitable for use with the coupling.
Numerous mounted implements for use on tractors have movable parts, which require a drive-energy source in order to be driven. The drive energy required for such a mounted implement is typically tapped from an engine of the tractor, e.g., via a P.T.O. shaft or via hydraulic fluid, wherein this hydraulic fluid is driven by a pump on-board the tractor and circulates in high-pressure lines and low-pressure lines of the tractor and the mounted implement. These lines must be disconnected from one another and reattached to one another every time the mounted implement is replaced on the tractor.
Hydraulic systems for tractors have become known under the name Power-Beyond™, in which the pump throughput is automatically controlled on the basis of the demand by the connected consumers. The pump of such a system runs continuously with the tractor engine in order to continuously maintain a high pressure in the high-pressure line, even when consumers do not draw hydraulic fluid from the high-pressure line. The high pressure must be maintained in order to ensure that, when a consumer begins to draw hydraulic fluid, the pressure in the high-pressure line can decrease and induce a resupply of the quantity pumped by the pump.
The need to have the pump run continuously with the engine also has disadvantages. Since the high pressure is constantly present all the way into the mounted implement, even when the mounted implement is not operating, e.g., while the tractor is traveling on the road, it is possible for hydraulic fluid to be continuously lost at a leaky point. Although the use of self-closing shutoff valves (also referred to as quick-release couplings) on high-pressure and low-pressure connections (which are intended to be connected to one another), of the vehicle and the mounted implement make it possible to disconnect the connections from one another while the engine is running without this resulting in the release of hydraulic fluid, it is necessary to open the shutoff valve of the high-pressure connection on the vehicle against the pressure present there in order to reconnect the aforementioned connections.
The physical strength of an operator is often insufficient therefor, in particular in the case of large line cross-sections. In addition, there is a great risk that, when the shutoff valve opens, the lines of the tractor and the mounted implement will not yet be fixedly connected to one another and hot hydraulic fluid will emerge and injure the operator. When the operator of a tractor comprising a Power-Beyond™ hydraulic system wants to replace a mounted implement that is driven by this hydraulic system with another mounted implement, he generally has no choice but to shut off the engine. In the case of modern vehicles equipped with complex electronic systems in particular, working time is lost, disadvantageously, when the engine is restarted, since the electronics must be powered up.